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BLAS VEGAS, NV - NOVEMBER 17: Actress Alison Sweeney (CL) runs in the Zappos.com 1/2 of the half race during the Rock 'n' Roll Las Vegas Marathon and Half Marathon benefitting the Crohn's & Colitis Foundation of America on November 17, 2013 in Las Vegas, Nevada. (Photo by Isaac Brekken/Getty Images for Competitor Group)

Celebrity Super-Athletes

Making it in Tinseltown takes some serious blood, sweat, and tears ... and so does participating in endurance races! Check out some celebrity super-athletes.